Re: Microsoft Surface
I've first seen some concepts like these in development the beginning of this year and I'm impressed Microsoft is putting something like this on the market already.
I really love the thing with the phones/camera/creditcard. You can just trow your device on the screen and the options are presented to you and you can drag the items across the screen.
I think this way of presenting and manipulating information is a good step in making the digital world more accessible to people who are not that tech savvy. It looks very intuitive to me.
The identifying of devices is probably done using RFID, so if you can put an RFID tag in an exercise sheet you could load the answers if they are present somewhere.